Intracutaneous injector with controlled entrance angle



Nov. 28, 1961 M. s. COOPER 3,

INTRACUTANEOUS INJECTOR WITH CONTROLLED ENTRANCE ANGLE Filed Aug. 29, 1960 IN V EN TOR. Ml/fEAYW COO/ 56 United States Patent Ofiice 3,010,455 Patented Nov. 28, 1961 This invention relates to an intracutaneous injector for the administration of biologically-active preparations,

which injector has a U-shaped spring, on one arm of which is a positioning foot plate, having a gap therein, to position the injector adjacent the skin and hold the skin in position, and on the other arm of which is a skin penetrating point, the penetrating angle of which is controlled by the U-shaped spring, which point penetrates the skin at a comparatively flat angle, and on which, at the time of use, is a biologically-active material.

Certain biological agents, which are either living organisms or are derived from living organisms, are used in either a nearly dry or liquid form for the diagnosis, prevention or treatment of diseases. Certain of these, in-

" cluding viral and bacterial vaccines, a viral and bacterial antigens, antibacterial and antitoxic antiserums, pollen extracts, and protein extracts, are frequently administered through the skin by scarification, subcutaneous injection, and intradermal injection.

For example, among the present methods of vaccination for smallpox, a drop of smallpox vaccine is placed on the cleansed skin of the subject, and a needle point is repeatedly pressed through the active liquid and into the skin adjacent carrying with it part of the vaccine. Such a method of administration is comparatively slow, and requires skill.

For rapid treatment, particularly with large numbers of subjects to be vaccinated, or with a large number of antigen tests on one subject, there is a demand for an intracutaneous injector which is so inexpensive that it can be used but once, and discarded, and which gives quick and accurate dosage employing the biologicallyactive material, in either nearly dry or liquid form, and which preferably can be used by inexperienced personnel.

Various multiple-point devices have been developed to give a multiplicity of abrasions or small cuts in a single operation. Some of these have no method of depth control other than the skill of the user. Others, such as shown in United States Patent No. 2,893,392, A. R. Wagner and M. S. Cooper, Article of Manufacture for Intracutaneous Injections, have a plurality of sharp points or prongs protruding from a plate which gives control over the depth of penetration of the prongs and which is designed to have the biologic carried into the skin of the subject by the action of the prongs.

It has now been found that a one-piece intracutaneous injector giving excellent results can be bent from a single piece of flat metal, in which one part of the metal is a foot plate in which there is a skin positioning gap, either a hole or a slot, and on the other end of which is a skin penetrating prong. The part between serves as a U- shaped spring to position the prong with respect to the skin positioning gap. A single prong may be used, but preferably two prongs are bent together so that there is a narrow slot which, by capillarity, attracts and holds a biologically-active material. The two prongs may have almost any angle between them, and are bent so that the prongs penetrate approximately parallel to the surface of the skin. The prongs may either be nearly parallel to the surface of the skin, or at a considerable angle, but their line of motion is such that the scarification or skin penetration occurs substantially parallel to the skin surface so that the biologically-active material is carried beneath the skin, but does not penetrate deeply into the tissues. The exact depth of penetration can be controlled by the length of the prongs, the size of the skin positioning gap, and the angle of attack, to give the degree of penetration which is desired for a particular biologicallyactive material. For some antigens, the preferred contact is in the area of the inner skin layers.

It is convenient to package the injector in a sealed, sterile, transparent package and discard the applicator after a single use so that there is no problem of contamination or of cleansing the instrument.

The penetration of the prongs can either be controlled by the dexterity of the operator, or a penetration depth guide may be formed into one side of the U-shaped spring so that the two sides contact and further penetration is thus prevented when the prongs have reached the desired depth.

Among the biologics which may be administered are Old Tuberculin and smallpox vaccine and diagnostic agents for allergens. The above-mentioned patent (2,893,392) discloses some such biologics which may be administered with the present device, including those for tuberculin tests, tetanus sensitivity, diagnosis of histo? plasmosis, blastomycosis, coccidioidomycosis, cryptococcosis, sporotrichosis, allergen sensitivity, smallpox vaccination, and many other purposes wherein intracutaneous injection of a biological is desired.

Certain illustrative modifications of the present invention are shown in the accompanying drawing in which:

FIGURE 1 is a plane view of the unbent injector as cut from sheet metal stock.

FIGURE 2 is a view of the bent injector assembled in a package.

FIGURE 3 is a side view of the injector of FIGURES l and 2.

FIGURE 4 is a view of a modification having a side entry slot, and a depth control guide.

FIGURE 5 is a partial view of a foot plate having an aperture showing the penetration of double prongs into the skin of the subject.

The injector is conveniently formed from non-corrosive metal stock such as stainless steel, or nickel alloy, or aluminum. For stainless steel, the injectors are conveniently formed from stock about 0.005-inch to about 0.015-inch thick. With thinner stock, the prongs are easily bent and the spring is weaker than is usually desired. With thicker stock, the materials cost is higher, and the additional strength is not necessary. Larger devices are useful for the administration of biologicallyactive material to animals having tough skin or thick fur.

The injector is cut from sheet stock as a forming blank 11, as shown in FIGURE 1. One end of the blank is bent as the foot plate 12. As shown, the foot plate portion has a slot 13 therein. The foot plate is bent on a bend line 14. The foot plate also has a skin puckering hump 15, bent into it, which is the form of a slight U to aid in causing the skin to pucker up in the slot for ease of penetration. The foot plate 12 is bent at about right angles to the U-shaped spring portion 16. The U-shaped spring is the main length of the forming blank, which is bent into a U-shape. At the opposed end of this U-shaped portion are the penetrating prongs 17. These prongs are conveniently symmetrical and are cut with an angle between them of between 5 and The prongs are bent along a prong bend line 18 so that one side of each prong is adjacent to the other prong, and the combined prongs form an angle with the arm of the U-shaped spring. The gap between the prongs is comparatively slight, and may be almost non-existent as even if the prongs are touching, the biologically-active liquid is may be almost as flat as the nibs of a pen, but preferably have a narrower angle, like a V, therebetween, so that the gap holds a larger quantity of thebiologicallyactive material. The final bend is as is shown in FIG- URE 3 so that the prongs mov e approximately parallel to the foot plate, and penetrate that portion ofthe skin which is puckered up in the skin positioning gap. The angle between the prongs and the arm of the U is conveniently from about 90 to 175. are used for a flatter angle of attack where a larger dose is desirable, and the wound is to be penetrating rather than scarifying.

In FIGURE 4 is shown a modification in which the foot plate has a lateral slot 19 and in which one arm of the U-shaped spring has a penetration depth guide 26. The penetration depth guide is conveniently, but not necessarily, a fold in one arm of the U to give a gaide of such length that the guide bridges the gap between the arms of the U-shaped spring when the penetrating prongs have reached a desired depth. A separate guide can be used.

As shown in FIGURE 5, the skin positioning gap may be an orifice 21. Usually, the orifice is somewhat larger than a slot so that the skin may press up through the orifice as the applicator is pressed against the skin of the subject. In FIGURE 3, the skin of the subject is shown including a skin hump 23 which is formed in the slot. In FIGURE 5, the prongs are'shown penetrating into a skin hump carrying with them the biologically-active material 24.

The injector is conveniently stored in a sterile, plastic package 25. Conveniently, the package is transparent so that its contents may be observed. It is preferred that the package have a strippable seal 26 so that one side of the package may be torn off without contaminating the contents of the package. The package may conveniently be a blister formed from a flat plastic sheet with the strippable seal sheet sealed to the rim of the other sheet around the blister.

The injector is formed by conventional metal-bending techniques.

For certain biologically-active materials which consist of killed viruses, or resistant viruses, the biologicallyactive material may be placed on the prongs in liquid form, and the injector placed in the package, the package sealed, and then sterilized by irradiation or by using a sterilizing gas such as ethylene oxide, or propylene oxide, or a mixture thereof, which will penetrate the plastic of the package and sterilize the contents. A suitable diluting gas such as carbon dioxide or a halohydrocarbon is used to prevent explosions.

Many biologically-active materials cannot stand either The smaller angles irradiation or an ethylene oxide sterilizing cycle, as any cycle which would inactivate conta' inants would also inactivate the biologically-active material. For such materials, the injector is sterilized by heat, radiati sterilizing agent, the package components are st and under sterile conditions the biologically rial is placed on the prongs, partially dried if desired (as by freeze-drying) and the injector is placed in the package and sealed, us ng sterile techniques throughout.

The injector is particularly convenient for suc logically-active materials as smallpox vaccine, in i the vaccinia is placed on the pr ngs under sterile conditions and stored in the packages assembled, as above de scribed, until ready for use.

It is to be understood that the particular biologicallyactive material being used is not per se a part of the present invention, and any biologically-active material which is to be administered in small quantities subcutaneously may be used with the present injector.

'For small doses, a single prong may be used. The biologicall -active material may be placed on the prongs just before administration, rather than stored thereon.

(Ether various modifications in the exact size and shape are obvious to those skilled in the art, the invention being defined by the following claims.

I claim:

1. A one-piece intracutaneous injector comprising: a foot plate, a skin-puckering hump and a' skin positioning slot therein, two adjacent, slightly spaced, pointed, penetrating prongs, a U-shaped spring connecting said foot plate and said penetrating prongs to position said penetrating prongs adjacent to but spaced from said skin positioning gap, but in a position to be pressed into penetrating contact With skin in said positioning gap, and a biologically-active material in said prongs.

2. A one-piece intracutaneous injector comprising: a foot plate, askin-puckering hump, and a skin-positioning slot therein, two adjacent, slightly spaced, pointed, penetrating prongs, to retain a liquid therebetween by capillarity, a U-shaped spring connecting said foot plate and said penetrating prongs to position said penetrating prongs adjacent to but spaced from said skin positioning gap, but in a position to be pressed into penetrating contact with skin in said positioning gap, a penetration depth guide formed in one side of said U-shaped spring to contact the other side of the spring, and control the depth of penetration of said prongs, and a liquid, biologicallyactive material on said prongs.

References Cited in the tile of this patent UNITED STATES PATENTS 2,546,759 Lee et al Mar. 27, 1951 2,639,691 Zurlo May 26, 1953 2,781,760 Baer Feb. 19, 1957 2,811,969 Shubert Nov. 5, 1957 2,861,318 Fernberg Nov. 25, 1958 

